The clinical data, diagnose and treatment of a child with familial glucocorticoid deficiency (FGD) caused by the NNT gene mutation who was treated in the Department of Endocrinology, Children′s Hospital Affiliated to Nanjing Medical University in November 2014 were retrospectively analyzed.The female child with 1 year and 5 months old presented with 6 months of skin pigmentation.Laboratory examinations showed decreased cortisol and increased adrenocorticotropic hormone.During the follow-up period, she developed convulsions and precocious puberty.Whole exome sequencing revealed that the patient carried a homozygous mutation c. 1054G > A (p.G352R) in exon 8 of the NNT gene, which was a newly reported gene mutation.Domestic cases of FGD caused by the NNT gene mutation has never been reported yet.Through literature review of a total of 40 reported children with FGD caused by the NNT gene mutation, typical manifestations included skin pigmentation, hypoglycemia and seizures, alongside mineralocorticoid deficiency, precious puberty, abnormal male gonadal development, thyroid diseases and heart diseases.